Combining Boundary Scan and in Circuit Testing Coverage Metrics
Combining boundary scan and in-circuit testing metrics requires mapping per-pin PCOLA-SOPS access, deduplicating overlapping faults, and logging verified nets for batch release.
PCOLA SOPS
Evaluation Metric
Scoring frameworks evaluate the effectiveness of assembly testing by measuring the detection capability for specific defect types. Industry standards use a standardized set of criteria to assign a numerical value to test coverage. The pcola sops method divides the assessment into two parts, where the first five letters track the physical presence and orientation of parts.
It measures whether the test can see the component, identify its value and verify its alignment.
Coverage Analysis
Secondary metrics focus on the electrical and functional integrity of the joints and the device itself. The second part of pcola sops addresses whether the pins are soldered and if the device actually functions. By combining these scores, a test engineer calculates a percentage of the total possible faults that the current test strategy will catch.
This calculation highlights gaps where a board might pass a test while still carrying a hidden defect. High scores indicate a process that leaves very little to chance during the final inspection stages.
Process Improvement
Comparing different test platforms becomes easier when their capabilities are mapped to this common scale. While an automated optical inspection system might score high on the first half of pcola sops, it usually requires a complementary electrical test to address the second half.